Method for preventing the sliding or riding up of packaged articles by coating with adhesive compositions

ABSTRACT

An aqueous colloidal adhesive composition for preventing sliding or riding up of packaged articles having coverings of paper, cardboard or pasteboard comprising an aqueous colloidal solution containing from 0.1 to 2 percent by weight of xanthan gum and the method of preventing sliding ro riding up of packaged articles which comprises interspersing between said package articles, a layer of said aqueous colloidal adhesive composition.

United States Patent [1 1 Sebel [54] METHOD FOR PREVENTING'THE SLIDINGOR RIDING UP OF PACKAGED ARTICLES BY COATING WITH ADHESIVE COMPOSITIONS[75] Inventor: Hans-Georg Sebel, Dusseldorf, Germany a [73] Assignee:Henkel & Cie Gmbl-I, Dusseldorf,

Germany 22 Filed: Aug. 25, 1970 21 App1.No.: 66,862

52 user. ..156/309,l56/336,117/156,

214/10.5 R, 106/205 511 Int.C l. ..C09j5/00,C09j 7/00' 58 Field bfSearch ..106/205, 209;

117/155 UA, 156, 157; 156/290, 291, 336, 309; 161/146, 148, 246, 250;2l4/10.5 R

[451 May 22, 1973 3,376,282 4/1968 I Schweiger 106/209 X 3,455,705 7/ l969 Rusher 106/209 X 3,428,464 2/1969 Pollard 106/209 X 2,793,966 5/1957Davis 117/156 X 2,808,381 10/1957 Stone 117/156 X 2,256,024 9/1941 Hill..214/10 5 2,702,642 2/ 1955 Bensinger ..214/10 5 3,045,802 7/1962Miller 214/ 10.5 X 3,059,787 10/1962 Forsyth ..214/6 3,598,677 8/ 1971Bergmeister et a1 ..156/327 X Primary Examiner-William D. MartinAssistant Examiner-M. R. Lusignan Attorney-Hammond & Littell [57]ABSTRACT An aqueous colloidal adhesive composition for preventingsliding or riding up of packaged articles having coverings of paper,cardboard or pasteboard comprising an aqueous colloidal solutioncontaining from 0.1 to 2 percent by weight of xanthan gum and the methodof preventing sliding ro riding up of packaged articles which comprisesinterspersing between said package articles, a layer of said aqueouscolloidal adhesive composition.

6 Claims, No Drawings Iler ..l17/15'6X I METHOD FOR PREVENTING THESLIDING OR RIDING UP OF PACKAGED ARTICLES BY COATING WITI-I ADHESIVECOMPOSITIONS THE PRIOR ART It is known to prevent the sliding of packingmaterials during transport on flat pallets by inserting adhesive betweenthe surfaces of the packages which are in contact. Aqueous alkali metalsilicate solutions, starch solutions, rubber or natural resindispersions and polymerizate dispersions can be used as adhesives, whichhave a film formation temperature of not more than C. Such productsgenerally have a good adhesive power, so that the stacked packages arefirmly connected together. However, this method has disadvantages whichare particularly to be seen in that smooth surfaces are glued too firmlyand owing to this, damage to the glued surfaces occurs when the stackedpackages are taken apart. Moreover, when the said adhesives are used,there frequently remains so much adhesive on the surfaces that thepackages are given a poor appearance. Finally, the said adhesives do notprevent sliding after the packages have been separated. However, this isoften desirable when restacking.

OBJECTS OF THE INVENTION An object of the invention is the obtention ofan aqueous colloidal adhesive composition for preventing sliding orriding up of packaged articles having coverings of paper, cardboard orpasteboard which has, on drying, a fairly low shear strength and peelingstrength and a relatively high coefficient of friction when the packagedarticles are restacked.

Another object of the present invention is the obtention of an aqueouscolloidal adhesive composition for preventing sliding or riding up ofpackaged articles having coverings of paper, cardboard or pasteboard,comprising an aqueous colloidal solution containing from about 0.1 to 2percent be weight of xanthan gum.

A further object of the invention is the development of a method forpreventing the sliding or riding up of packaged articles havingcoverings of paper, cardboard or pasteboard, which comprisesinterspersing between said packaged articles, a layer of from 25 to 500gm/m of an aqueous colloidal adhesive composition containing from about0.1 to 2 percent be weight of Xanthan gum, and drying said layer.

These and other objects of the invention will become more apparent asthe description thereof proceeds.

DESCRIPTION OF THE INVENTION According to the invention, there isprovided an,

aqueous collidal adhesive composition for preventing sliding or ridingup of packaged articles having coverings of paper, cardboard orpasteboard comprising an aqueous colloidal solution of xanthan gum. Thexanthan gums are advantageously utilized as from about 0.1 to 2 byweight solutions.

By xantham gum is meant a polysaccharide which is built up essentiallyfrom glucose, mannose, the potassium salt of glucuronic acid and acetylgroups in the approximate molar ratio of 2:l:1:l. It contains furtherminor amount of chemically bound pyro-racemic acid. The preparations ofXanthan gum is known (cf. Journal of Biochemical and MicrobiologicalTechnology and Engineering, Vol III, No. l (1961) p. 51-63). It takesplace in known way by the action of the strain of bacterial Xanthomascampestris on aqueous solutions of glucose of starch.

Xanthan gum is a substance readily soluble in water. A 2 percent aqueoussolution has at 20C a viscosity between about 2,500 and 10,000 cP. Thesolutions of Xanthan gum are extremely stable towards the addition ofchemicals.

According to one form of the invention, in addition to the xanthan gumin the adhesives, further watersoluble colloids such as celluloseethers, starch products or alginates may be added. Suitablewater-soluble cellulose ethers are, for example, methylcellulose,hydroxyethylcellulose, hydroxypropylcellulose,methylhydroxy-propylcellulose and others. Suitable starch products arewater-soluble starch degradation products such as, forexample,water-soluble starch or its substitution products such asmethyl-starch or carboxymethyl starch. Suitable water-soluble alginatesare, for example, sodium or ammonium alginate. The quantity of thesecolloids, however, should not exceed a content of from 0.1 to 0.5percent by weight, based on the total mixture.

Besides the natural water-soluble colloids mentioned, the adhesivesaccording to the invention may additionally contain water-solublepolymerizates such as polyvinyl ether, polyvinylpyrrolidone or polyvinylalcohol. The K-value of such polymerizates should lie between about 20and 80, and it is advantageously used in an amount from 1 to 15 percentby weight, based on the total mixture. The co-use of polyvinyl methylether having a K-value of from 20 to 60, preferably. about 40, in theindicated amount, is especially advantageous the preparation of theadhesives according to the invention. j

In some cases it has also been found suitable to add from 0.1 to 10 byweight of inorganic or organic fillers to the adhesives. Inorganicfillers of this kind are, for example, finely divided silicic acid orcalcium silicate or aluminum silicate. The organic fillers used may be,for example, starch or ground cellulose as well as hardened and groundmelamine resins or urea resins. The use of finely-divided silicic acidas an additive is especially favorable. Owing to the high viscosity andthixotropy of the xanthan gum, the adhesives can be easily made, andsince the xanthan gum has a high carrying capacity for fillers,relatively large amount of the inorganic or organic fillers mentionedmay also be incorporated in the adhesives. V

In many cases, a very favorable result is obtained by adding to theadhesives about 0.5 to 5 percent by weight of a poly-hydric alcoholand/or polyalkylene glyeols. Suitable poly-hydric alcohols are, forexample, lower alkane-polyols such as glycol, glycerine, trimeth+ylolpropane, mannitol, sorbitol and the like. Also the term polyhydricalcohol" is to be understood in the wider sense to include sugars suchas glucose, laevulose or cane sugar. Suitable polyalkylene glycols areespe& cially diethylene glycol, triethylene glycol and the additionproducts of ethylene oxide to ethylene glycol up to a molecular weightof about 800, and the still water soluble addition products of propyleneoxide to lower alcohols. Suitable additives are finally thepolymerization products of glycerine, which are formed by etheri-.fication of 2 to about 12 glycerine molecules with one another.

In order to protect the adhesives against bacteria] breakdown, knownpreservatives may be added to them. Those which are used are principallythose which are compatible with xanthan gum and the other additives. Forexample, formalin, pentachlorophenolates, p-hydroxybenzoic acid esters,which are on the market spindle 3 in 1 percent aqueous solution) and wasdissolved with stirring in each case in so much water that, afteraddition of the further substances, all the components including wateradded up to 100. In the following under a variety of names, aresuitable. 5 Table l, the first column gives the number of the exam- Theadhesives, according to the invention, may be ple, and there follow thepercentage by weight of xanused during the stacking of substances packedin paper than gum, polyvinyl methyl ether (K-value 40), and or cardboardwhich during loading or transport must further colloids and fillers aswell as the hardness of the not be allowed to ride up, slide off orshift relative to water used according to German degrees of hardness.

TABLE I Xanthan methylgum/ ether/ Hard- Number percent percent Furthercolloids/percent Fillers, percent ness 0.5 10 0.4 0.3methylhydroxypropylcellulos 16 0.7 0.1 carboxymethylcellulose 16 0.4 0.2Na-alglnate 10 0.7 2.0finely-dispersed l0 0. 2.0 finely-dispersed silit0.3 5. 0 0.2 Naalgiuate U 0.2 5.0 0.2 Na-alginate, 0.1 hydroxypropylcellulose 10 0.3 5.0 0.3 polyvinylpyrrolidone 10 These solutions may bediluted or use by two to four times.

one another. The adhesives, according to the invention are used withparticular advantage in the case of shipping cartons or packings withsensitive surfaces. They may also be used, however, for fixation ofpaper bags or cartons of solid fiberboard and corrugated board.

For the preparation of the adhesives,according to the invention, thexanthan gum is first dissolved in water with stirring in known way. Theother components are then added with further stirring. If the pH valueis displaced outside of pl-l6 to pH8 by the individual components, it isadjusted again to fall within the said range by the addition of acid oralkali.

For the application of the adhesives, according to the invention, theseare applied by brushing, rolling or spreading, e.g., painting. It hasbeen found especially suitable to apply them by means of jets in dots orstrips on the surfaces to be treated. Preferable, the adhesivecompositions of the invention are applied in amounts of from to 500 gm/mImmediately after the application, the adhesives according to theinvention become active. On the one hand, a certain sticking actionexists, and on the other hand they have as a result after evaporation ordriving off of the water, a surface equipped to prevent sliding. Thiseffect also remains when the stacks have been taken apart and rebuiltagain. With the adhesives according to the invention a problem wassolved in which two opposed properties were to be brought in unison withone another. On the one hand a resistant union between the stackedpackages and the base had to be effected, but on the other hand thisunion was not to be so firm that, on separating the stack, damage to thesurface resulted. Moreover, after separating the stack, the adhesive onthe surface had to be practically no longer perceptible.

The present invention will be further described, by way of reference tothe following examples which are not to be deemed limitative.

EXAMPLES Commercial xanthan gum was used (viscosity 3300 c? according toBrookfield RVT at 20C and 20 Rpm,

For the examples 1 to 13 the shearing strength (kp/cm the peelingstrength (gm/ 10 cm) and the coefficient of friction of the adhesivecompositions as applied to paper were measured.

For the measurements, paper was used as conventionally a-plied for themanufacturing of paper bags. Two types of paper were employed, one was asoda kraft paper of gm/m the other was a wet-strength kraft paper of 73gm lm The latter was slightly crimped. For the examination, each time somuch of the adhesive agent was applied with a sizing comb so that anaverage coat of gm/m was attained. Subsequently, the papers were stackedabove each other, namely a treated one on an untreated one, and loadedwith a brick so that an average pressure of 15 gm/cm was attained. Afterstoring for 24 hours at a room temperature of about 2325C themeasurements were taken.

For the examination of the shearing strength, the papers were pulledapart in a conventional tearing machine.

For the examination of the peeling strength, the papers were drawn apartalso in a tearing machine whereby the peeling angle was almost 180.

The coefficient of friction was measured in that the pulled apart paperswere stacked one above the other, and the friction coefficient wasdetermined with a load of 20 gm/cm and a moving speed of 10 cm perminute. In the following Table II, the first column gives theconsecutive number of the example, the second column gives the kind ofpaper (NK=soda kraft paper; LK= wet strength, slightly crimped kraftpaper). The following columns give the shearing strength in Kp per cm*,the peeling strength in gm/ 10 cm and the coefficient of friction.

TABLE ll Coefficient Shear Peeling of friction Paper strength strengthof peeled Ex. No. type (Kp/cm) gm/lO cm samples I NK 1.8 300 0.55 LK 0.80.6 Zn NK 2.3 400 0.5

LK 2.9 250 0.6 3 NK 0.5 50 0.55 LK 0.1 20 0.55 4 NK 0.8 100 0.7 LK 0.120 0.6 5 NK 2.0 100 0.5 LK 2.5 20 0.4 6 NK 2.0 200 0.5 LK 2.3 100 0.5 7NK 400 0.5 LK 2 8 200 0.4 8 NK 1.3 250 0.5 LK 0.1 400 0.4 9 NK 0.2 3001.0 LK 0.1 150 0.8 10 NK 0.1 250 0.8 LK 0.1 100 0.7 1 l NK 0.5 200 1.25LK 0.1 20 1.4 12 NK 0.6 250 1.0 LK 0.2 50 0.6 13 NK 0.7 250 0.9 LK 0.250 0.6

EXAMPLE 14 Strips of the adhesive composition of Examples 1 to 13 of 15cm width were applied lengthwise to the middle of one side of paper bagsfilled with powdered material, utilizing an adhesive applicator whichapplied strips of adhesive through a series of jet orifices at anapplication rate of 100 gm adhesive per 1 m of the paper bag surface.The paper bags were stacked and palletized. After shipping, the paperbags were received in their original stack without any sliding betweenthem. They were readily separated without tearing of the surfaces. Thepaper bags could be restacked and when restacked, retained goodadherence.

The preceding specific embodiments are illustrative of the practice ofthe invention. It is to be understood, however, that other expedientsknown to those skilled in the art may be employed without departing fromthe spirit of the invention or the scope of the appended claims.

1 claim:

1. In a method for preventing the sliding or riding up of packagedarticles having coverings of paper, card board or pasteboard, whichcomprises applying a layer of adhesive material to the surfaces ofpackaged articles, drying the layer and placing the packaged articles incontact, the improvement which comprises utilizing as said adhesivematerial, a layer of from 25 gm/m to 500 gm/m of an aqueous colloidaladhesive composition consisting essentially of from about 0.1 to 2percent by weight of xanthan gum.

2. In a method for preventing the sliding or riding up of packagedarticles having coverings of paper, cardboard or pasteboard, whichcomprises applying a layer of packaged articles having coverings ofpaper, card- I board or pasteboard, which comprises applying a layer ofadhesive material to the surfaces of packaged articles, drying the layerand placing the packaged articles in contact, the improvement whichcomprises utilizing as said adhesive material, a layer of from 25 gm/mto 500 gm/m of an aqueous colloidal adhesive composition consistingessentially of (a) from about 0.1 to 2 percent by weight of xanthan gum,(b) from 1 to 15 percent by weight of polyvinyl methyl ether having aK-value of from 20 to 60, and (c) from 0.1 to 10 percent by weight of afiller.

4. The method of claim 3 wherein saidfiller is finely divided silicicacid.

5. In a method for preventing the sliding or riding up of packagedarticles having coverings of paper, cardboard or pasteboard, whichcomprises applying a layer of adhesive material to the surfaces ofvpackaged articles, drying the layer and placing the packaged articles incontact, the improvement which comprises utilizing as said adhesivematerial, a layer of from 25 gm/m to 500 gm/m of an aqueous colloidaladhesive composition consisting essentially of from about 0.1 to 2 percent by weight of xanthan gum; separating said packaged articles withoutdamaging the adhesive coated surfaces thereof.

6. The method of claim 5 wherein the improvement further comprises thestep of restacking said separated packaged articles by bringing theadhesive coated surfaces into unison with one another.

. NUNIT ED STATES PATENT OFFICE CERTIFICATE OF CORRECTIQN Patent No.5,734,801 Dated ay 22, 1973 lnv entofls) Hans 'GeoTg Sebel It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

the Title, Column 1, after Appln. No. 66,862 insert Claims, Priorityapplication Germany, August 28, 1969 No P 19 43 731.1 In the ABSTRACT,line 6,- "r0" should read or Column 1 line 60 "Xantham" should readExanthan Column 4, line 31, "a-plied" should read applied Signed andsealed this 27th day of August 1974.

SEAL Attestc MCCOY M. GIBSON, JR. 0. MARSHALL DANN Attesting OfficerCommissioner of Patents FORM Po-1dso (IO-69) USCOMWDC 603764,

I I US. GOVERNMENT PRINTING OFFICE I9. 0-366-33,

2. In a method for preventing the sliding or riding up of packaged articles having coverings of paper, cardboard or pasteboard, which comprises applying a layer of adhesive material to the surfaces of packaged articles, drying the layer and placing the packaged articles in contact, the improvement which comprises utilizing as said adhesive material, a layer of from 25 gm/m2 to 500 gm/m2 of an aqueous colloidal adhesive composition consisting essentially of (a) from about 0.1 to 2 percent by weight of xanthan gum, and (b) from 1 to 15 percent by weight of polyvinyl methyl ether having a K-value of from 20 to
 60. 3. In a method for preventing the sliding or riding up of packaged articles having coverings of paper, cardboard or pasteboard, which comprises applying a layer of adhesive material to the surfaces of packaged articles, drying the layer and placing the packaged articles in contact, the improvement which comprises utilizing as said adhesive material, a layer of from 25 gm/m2 to 500 gm/m2 of an aqueous colloidal adhesive composition consisting essentially of (a) from about 0.1 to 2 percent by weight of xanthan gum, (b) from 1 to 15 percent by weight of polyvinyl methyl ether having a K-value of from 20 to 60, and (c) from 0.1 to 10 percent by weight of a filler.
 4. The method of claim 3 wherein said filler is finely divided silicic acid.
 5. In a method for preventing the sliding or riding up of packaged articles having coverings of paper, cardboard or pasteboard, which comprises applying a layer of adhesive material to the surfaces of packaged articles, drying the layer and placing the packaged articles in contact, the improvement which comprises utilizing as said adhesive material, a layer of from 25 gm/m2 to 500 gm/m2 of an aqueous colloidal adhesive composition consisting essentially of from about 0.1 to 2 percent by weight of xanthan gum; separating said packaged articles without damaging the adhesive coated surfaces thereof.
 6. The method of claim 5 wherein the improvement further comprises the step of restacking said separated packaged articles by bringing the adhesive coated surfaces into unison with one another. 